#include <stdio.h>
int main()
{
	int a=10,b=20,s,t,*pt_a,*pt_b;			
	pt_a=&a;							
	pt_b=&b;							
	s=*pt_a+*pt_b;					
	t=*pt_a * *pt_b;					
	printf("a=%d  b=%d  a+b=%d  a*b=%d\n",a,b,a+b,a*b);		
	printf("s=%d  t=%d\n",s,t);			
	return 0;
}
